How many holes can you poke in this? And do they really matter?

Object.defineProperty Shim.js

if (!Object.defineProperty) {
  if (Object.__defineGetter__) {
    Object.defineProperty = function(obj, name, options) {
      if (!options) throw new Error("`options` is a required argument.");

      if ("get" in options || "set" in options) {
        if ("get" in options) {
          obj.__defineGetter__(name, options.get);
        }
        if ("set" in options) {
          obj.__defineSetter__(name, options.set);
        }
      } else if ("value" in options) {
          obj.__defineGetter__(name, options.value);
          obj.__defineSetter__(name, options.value);
      }
    };

    Object.defineProperties = function(obj, properties) {
      for (var name in properties) {
        Object.defineProperty(obj, name, properties[name]);
      }
    };
  } else throw new Error('Object.defineProperty cannot be used or shimmed in this environment.');
}